Many vehicles are equipped with cargo racks for storing cargo during travel. Cargo racks can be configured to carry bikes, kayaks, skis, snowboards, canoes, luggage, storage containers, gear baskets, and/or a variety of other items.
Cargo that is loaded on a vehicle can increase the effective height of the vehicle. Therefore, a vehicle may not be able to safely pass under a low clearance area when cargo is loaded on the vehicle. Attempting to pass under a low clearance area can cause damage to the cargo, the cargo rack, the vehicle, and/or the low clearance area.
A driver can easily forget about height-extending cargo, thus increasing the risk that the driver will unknowingly attempt to drive under a low clearance area. Others have attempted to address this problem in a variety of different ways. For example, U.S. Pat. No. 6,737,960 to Preston discloses a warning system for detecting when a vehicle is approaching a remote transmitter which is pre-positioned near a low clearance area. The inventor herein has recognized that such an approach does not provide any warning if the vehicle is going to drive under a low clearance area at which a transmitter has not been pre-positioned, thus greatly limiting the effectiveness of the warning system. US Patent Publication No. 2004/0226205A1 to Kawakita discloses another approach, in which a visual indicator is positioned on a blinker/headlight control stick near a vehicle's steering wheel. The inventor herein has recognized that the warning mechanism of Kawakita does not position the warning in the driver's normal field of vision, nor is it configured so a driver is reminded to activate the warning when loading cargo on top of a vehicle.
At least some of these issues can be addressed by the herein disclosed cargo clearance warning systems, which can be configured to warn a driver when cargo is loaded on top of a vehicle and/or the vehicle is approaching a low clearance area. According to some aspects of this disclosure, a warning system can be used to position a reminder in a driver's field of vision so as to decrease the likelihood that overhead cargo is forgotten. Such a system can be designed so that a driver is reminded, if not required, when loading cargo to place a warning indicator in the driving field of vision. According to some aspects of this disclosure, a warning system can be configured to detect when cargo is loaded and/or when the vehicle is approaching a low clearance area. Such a system can be configured to identify low clearance areas that have not been specially marked, tagged, or otherwise identified beforehand.